Needle unsheathing, resheathing and handling apparatus

ABSTRACT

The present invention is principally directed to an apparatus for unsheathing, resheathing and handling needles. The preferred embodiment includes an elongated housing having an opening at one end that communicates with an internal chamber. Sheath retaining members are disposed substantially adjacent to the opening and can be employed for selective retaining engagement of a sheath that is inserted into the opening. The sheath retaining members may include a deflectable spring member. A gripping portion may be provided in connection with the housing. Appropriate use of the apparatus obviates the need for manual grasping of a needle sheath and provides additional advantages.

FIELD OF THE INVENTION

This invention relates to the unsheathing, resheathing and handling ofneedles, including without limitation syringe needles. Moreparticularly, the present invention is directed to a safe and convenientapparatus for selectively engaging and retaining needle sheaths, forholding needles and syringes during periods of non-use in multipleapplications, for sheathing needles after use, and for assisting in thedisconnection of sheathed syringe needles from syringe bodies and thedisposal thereof.

BACKGROUND OF THE INVENTION

Syringe needles are typically covered with protective sheaths prior touse, and it is desirable to resheath needles after use, includingresheathing during multiple syringe use applications, and for needledisposal purposes. Consequently, the unsheathing, resheathing anddisconnecting of sheathed needles from syringe bodies are procedureswhich are repeatedly carried out by doctors, nurses, technicians and thelike.

As readily appreciated by such individuals, the above-noted procedurescan become tedious and raise cross-contamination concerns, particularlywhen manual grasping of a sheath is required. Additionally, suchprocedures can result in "needle sticks", i.e., the inadvertent prickingof a hand. For example, needle sticks can occur when, during manualresheathing, a syringe needle misses the relatively small opening of asheath and pricks the hand in which the sheath is being grasped. While aneedle stick does not initially give rise to serious injury, the threatof communicating serious diseases, such as hepatitis and AIDS, is ofgreat concern.

Various approaches have been proposed to address the above-notedproblems. For example, syringes have been developed which include atelescoping shield member that can be selectively pulled over a syringeneedle after use. Another new syringe includes a needle that can beretracted into the syringe body after use. These products areprohibitively expensive for most applications, and have proven to besubject to leakage and other contamination problems.

Of particular importance, a number of independent apparatus forassisting in syringe needle unsheathing, resheathing and disposal havebeen proposed. For example, U.S. Pat. No. 4,485,918 to Mayer, disclosesa funnel-shaped apparatus, adapted to be hand-held by the tubularportion thereof. The tubular portion has a closed-end and is of alimited length so that, if the apparatus is held upright, a sheath canbe supported within the apparatus and reapplied to a syringe needle. Inaddition to the inconvenience associated with the required upwardorientation for sheath support and resheathing, it should be noted thatthe above-described Mayer apparatus does not include any features forselective removal of a sheath from a syringe needle.

Mayer further discloses a separate apparatus for assisting inresheathing and in the disconnection of a sheathed needle from a syringebody and the disposal thereof. Specifically, Mayer shows a box-shapedapparatus having an aperture in the ceiling with radially extendingslots. In use, Mayer proposes that a sheath can be manually insertedinto the aperture and supported about its flange by the adjacent ceilingportion. A needle can then be inserted into the sheath until resheathingis achieved. Mayer further proposes that a sheathed needle assembly canbe pressed through the aperture due to ceiling flex permitted by theslots, moved laterally to cause abutting engagement between the needlehub and the adjacent ceiling portion, and that the syringe body canthereafter be pulled, and if necessary, twisted upward to causedisconnection of the needle assembly from the syringe body. It should benoted that this apparatus is not adapted to be handheld and fails todisclose any features for selective removal of a sheath from a needle.In addition, the aperture/slot arrangement of the apparatus would seemto accommodate only certain sizes of sheaths for successful resheathingand disposal, and would appear to be particularly subject to wear.Further, the apparatus requires either mechanical anchoring or manualholding during needle disconnection procedures.

U.S. Pat. No. 4,596,562 to Vernon, and U.S. Pat. No. 4,717,386 toSimmons, both disclose apparatus for assisting in the unsheathing,resheathing and/or handling of syringe needles wherein means forretaining engagement of a sheath are employed. In particular, the Vernonand Simmons apparatus each require forcible entry of a sheath into arestricted opening to effectuate sheath engagement and retention by theperiphery of the opening.

For example, Vernon discloses a generally planar apparatus having atleast one hole therethrough of a diameter corresponding to a diameterfound along the length of typical tapered sheaths. Vernon alsocontemplates the provision of a slot at the top end of the disclosedapparatus, defined by two parallel, spaced plates, with a pie-shapedopening extending downward from one of the plates to accommodate accessto the slot. Vernon proposes that, at least for resheathing, a sheathcan be forced into either the opening or the slot until restrictiveengagement between the outer periphery of the sheath and the peripheryof the opening or slot occurs. A syringe needle can then be insertedinto the supported sheath until resheathing is achieved, andsubsequently removed from the apparatus by manual grasping and pullingof the sheath to cause disengagement. It is important to appreciate thatsuch a procedure necessitates the initial inward positioning of a sheathto a specific location within an opening to effectuate retention, andthe application of opposing forces to achieve both sheath engagement anddisengagement. Such requirements present particular operational problemswhen the apparatus is to be handheld. Further, significantcross-contamination can occur between a sheath and a user's hand orglove during manual disengagement of a sheath from the Vernon apparatus.Finally, the contemplated handle of the Vernon apparatus is spatiallyremoved from the proposed sheath retaining means, thereby contributingto needle/sheath alignment difficulties associated with resheathing.

In the disclosed Simmons apparatus, a cylindrical member with converginginner walls extends laterally away from a plate-like member. Simmonsproposes that by forcing a sheath into the opening of the cylindricalmember of the apparatus, restrictive engagement between the inner wallsof the member and the periphery of the sheath can be achieved. Uponconsideration, it is apparent that, as with the Vernon apparatus,initial sheath engagement necessitates specific sheath positioning andthe provision of opposing forces. In addition, disengagement of asheathed needle from the Simmons apparatus would entail the inconvenientgrasping of a sheath by a user and could result in undesiredcross-contamination. Further, it would seem that the sheath retainingmeans of the Simmons apparatus is particularly subject to significantwear as the result of the repetitive rubbing of sheaths against theinner-walls of the cylindrical member.

In view of the disadvantages corresponding with the above-noted,representative apparatus, it is apparent that a substantial need existsfor a safe and convenient apparatus for assisting in initial needleunsheathing, sheath retention, syringe holding, needle resheathing, andsheathed needle disconnection and disposal procedures. Such an apparatusis singularly provided by the novel features incorporated into thepresent invention.

SUMMARY OF THE INVENTION

The present invention comprises a housing having an opening at one endthat communicates with an internal chamber. The opening and chamber areadapted to receive typical needle sheaths. A sheath retaining means isdisposed within the housing chamber substantially adjacent to theopening and can be selectively actuated by a user to engage a sheaththat is inserted into the opening.

In one aspect of the present invention, the sheath retaining means mayinclude a spring means and an actuator means that can be selectivelyoperated by a user to mechanically effectuate desired movement of thespring means laterally away from and back towards the longitudinalcenter axis that passes through the housing opening. A seat memberhaving at least one and preferably two-spaced V-shaped supports can beprovided in an operative opposing relationship to the spring meanswithin the housing so that a sheath inserted into the housing openingcan be selectively and securely retained between the seat member andspring member. The spring means may be configured and disposed withinthe housing so that it is in deflected state with a portion thereofbearing against the seat member during periods of non-use. An unevenedge may also be provided on the spring member to contribute toeffective sheath retention.

In a further aspect of the present invention, the housing portion thatis substantially adjacent to the opening and surrounds a correspondingportion of the internal chamber is adapted to be gripped by the hand ofa user. Additionally, a portion of the actuator means can belongitudinally disposed within such gripping portion. Further, a shieldcan be provided adjacent to the gripping portion and may extendlaterally away from the housing opening.

Due to its novel design, as further described hereinbelow, the presentinvention yields various combined advantages with respect tounsheathing, sheath retention, sheathed needle-syringe holding,resheathing and sheathed needle disconnection and disposal.

For example, the retaining means of the present invention permits asheath to be selectively engaged and retained when the same is locatedat any position along a continuum of positions relative to the retainingmeans. That is, there is no requirement that the sheath be positioned atany single location to effectuate a retaining engagement. Rather a rangeof positions, as substantially defined by the length of a sheath, areacceptable to effectuate engaging retention.

With further respect to the retaining means of the present invention, itshould be appreciated that no forcible entry of a sheath within arestricted opening or forcible exit therefrom is required to effectuateretaining engagement or to effectuate disengagement. Stated differently,a user need not apply opposing push/pull forces to achieve retainingengagement or disengagement with the present invention.

Relatedly, it is important to realize that the preferred retaining meansof the present invention is relatively easy to actuate. In particular, anon-linear cantilever spring can be pivotally mounted within a rearwardportion of the housing and linearly disposed upon assembly. By virtue ofsuch linear disposition, the cantilever spring is in a deflected, biasedstate during periods of non-use, and further biasing of the spring toeffectuate sheath engagement or disengagement requires the applicationof only minimal forces by the user. That is, the preferred spring meansexhibits a low actuation force to deflection ratio. Further, it shouldbe noted that, when actuated to retainingly engage a sheath, theretaining means of the present invention equally restricts movement of asheath in either direction relative to the retaining means. This isparticularly important when unsheathing and resheathing procedures areconsidered.

Specifically, the retaining means of the present invention permits auser to unsheath and resheath a syringe needle inserted in the housingopening, and to remove a resheathed needle, without grasping orotherwise contacting the sheath with a user's hand. Since the presentinvention does not require such contact, convenience is maximized andattendant needlestick and cross-contamination concerns are significantlyreduced, thereby making the present invention particularly apt for usein surgical applications and in multiple syringe use applications.

In the latter regard, the elongated housing of the present inventionprovides an effective counter-weight when the apparatus is used to holda syringe during periods of non-use in multiple applications. Further,and as further described below, flat edges can be provided on the shieldof the inventive apparatus to prevent rolling when the apparatus isplaced upon a relatively flat surface, and the diameter of the shieldcan be selected so that the apparatus will have a desired upwardorientation when the apparatus is placed upon a relatively flat surface.These features enhance use of the apparatus for holding syringes duringperiods of nonuse, and allow for convenient grasping of the apparatusfor unsheathing, resheathing and other procedures.

In addition to the foregoing, the likelihood of needlestick is furtherminimized by the provision of the laterally extending shield.Additionally, convenient insertion of a sheathed or unsheathed syringeneedle into the housing opening and sheath engagement and/ordisengagement is provided by the present invention due to the spatialarrangement between the housing opening, the internal chamber thereofand the gripping portion of the housing. That is, the present inventionprovides an apparatus wherein insertion and sheath engagement and/ordisengagement does not occur at a location spatially removed from thehand of a user. In a preferred embodiment of the invention, convenientinsertion is further realized by providing a shield that isfrusto-conically shaped to receive and direct a sheathed or unsheathedneedle into the housing opening.

The inventive apparatus also advantageously provides an actuator memberthat can be conveniently operated by the palm or fingers of a user. Thispermits the apparatus to be utilized by those having small hands or arelatively weak grip.

Finally, it should be appreciated that the present invention furtherprovides for a safe and convenient method of disconnection of a sheathedneedle from a corresponding syringe body and for safe disposal thereof.Such advantages are provided since, as noted above, the retaining meansof the present invention restricts movement of a sheath in eitherdirection relative to the retaining means. More particularly, afterresheathing has occurred, a user may pull, and if necessary, twist asyringe body away from the apparatus to effectuate disconnection of thesyringe body from the sheathed needle assembly. Thereafter, theapparatus holding the sheathed needle can be carried to an appropriatedisposal receptacle and the actuator member can be depressed to drop thesheathed needle in the receptacle. As should be appreciated,disconnection and disposal can therefore be accomplished without contactbetween a user's hand and a sheath or needle assembly.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevated, perspective view of the preferred embodiment ofthe present invention.

FIG. 2 is a cross-sectional, side view at the longitudinal center axisof the preferred embodiment of the present invention.

FIG. 3 is a cross-sectional end view of the preferred embodiment of thepresent invention, at plane 3--3 shown in FIG. 2.

FIGS. 4A-4C illustrate use of one embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

For purposes of description herein, the terms "upper," "lower," "right,""left," "rear," "front," "vertical," "horizontal" and derivativesthereof shall relate to the invention as oriented in the preferredembodiments as exemplified in the drawings herein. However, it is to beunderstood that the invention may assume various alternativeorientations and step sequences, except where expressly specified to thecontrary. It is also to be understood that the specific devices andprocesses illustrated in the attached drawings, and described in thefollowing specification, are only exemplary of the inventive conceptsaddressed in the appended claims. Hence, specific dimensions, physicalcharacteristics, and procedures relating to the embodiments disclosedherein are not to be considered as limiting, unless the claims by theirlanguage expressly state otherwise.

The reference numeral 10 (FIGS. 1 and 2) generally designates apreferred embodiment of an apparatus embodying the present invention.The apparatus 10 is particularly adapted for use with syringes, such asthe syringe 12 illustrated in FIGS. 4B and 4C. As is conventional,syringe 12 includes a chamber 14, a plunger 16, and has a flange 18 onone end. On the other end of syringe 12 is a spigot 20 for receiving aneedle assembly 22 thereon. Needle assembly 22, which includes a needle24 and hub 26 is typically press or threadingly fitted onto spigot 20,and covered by sheath 28 when syringe 12 is not in use.

The preferred embodiment 10 (Figs. 1 and 2) includes a housing 30 havinga snap fitting 32, screw fitting 33 and defining recess 34. Housing 30is an elongate shell constructed of injection-molded plastic, having alength of approximately 4.8 inches. As will be appreciated by thoseskilled in the art, the housing 30 and other components of the preferredembodiment 10 may be constructed of appropriate materials to permitsterilization within typical autoclaves.

Housing 30 defines a gripping section 36 along its outer surface (FIG.2), adapted to be held by a user's hand (FIG. 4), and an internalchamber 38 therewithin. A sheath receiving aperture 40 (FIGS. 2 and 3),which communicates with internal chamber 38, is disposed at a front endof housing 30. In the present example, sheath receiving aperture 40 hasa diameter of approximately 0.4 inches, thus providing an opening withan area great enough to receive all typically employed sheath sizes.More specifically, sheath 28 can be easily passed through sheathreceiving aperture 40, without being hindered thereby. A sheathretrieving aperture 42, communicating with internal chamber 38, isdisposed toward the rear of housing 30.

An aperture 44 (FIG. 2) is defined within gripping portion 36 andreceives an actuator 46. While aperture 44 and actuator 46 are shown ina bottom portion of the preferred embodiment 10 in FIGS. 1-3, it shouldbe understood that aperture 44 and actuator 46 could also be disposed ina top portion, as illustrated in FIGS. 4A-C.

One end of actuator 46 is pivotally connected with a rear section ofhousing 30 through use of a pivot pin 48. In the present example, theconnection between actuator 46 and housing 30 is similar in design tothat of a conventional stapler. An end of actuator 46, disposed oppositeto the pivoted end, engages a cantilever spring 50.

Cantilever spring 50 has a first end 52 and a second end 54. A firstseat 56 of housing 30 is employed with screws 62 to secure first end 52of cantilever spring 50 to housing 30. Screws 62 pass through apertures70 in the first seat 56 and apertures (not shown) in the first end 52 ofthe cantilever spring 50. As will be appreciated by those skilled in theart, spring first end 52 could also be secured to housing 30 by way ofconventional rivets. As illustrated in FIG. 2, a cover plate 64 issnap-fitted over recess 34 by nubs 66 so that recess 34 is sealed offduring operation of the apparatus 10.

In the preferred embodiment 10, cantilever spring 50 can be fabricatedfrom stainless steel and configured so that, prior to assembly of device10, cantilever spring 50 is non-linear. In particular, in relation toFIG. 2, second end 54 may be disposed downward relative to first end 52prior to assembly. Upon assembly as shown in FIG. 2, second end 54 willthus be in a deflected (i.e., biased) state, bearing downwardly againstportion 72 of support seat 76. As a result of this arrangement, secondend 54 of cantilever spring 50 can be further deflected by theapplication of minimal actuation forces, as will be further discussed.

As noted above, second spring end 54 engages the front end of actuator46. In the present example, the front end of actuator 46, constitutingtwo "ear" portions 74 (FIGS. 2 and 3), engages the outer edges of secondend 54 of cantilever spring 50. A second seat 76 is operatively mountedwithin housing 30 near sheath receiving aperture 40 (FIGS. 2 and 3).When the preferred embodiment 10 is not in use, the aforementionedprestressing of spring 50 causes spring second end 54 to engage portion72 of second seat 76. As shown in FIG. 3 access through sheath receivingaperture 40 is blocked during non-use of the preferred embodiment 10.

In order to freely insert sheath 28 through aperture 40 and into chamber38 it is only necessary to depress actuator 46 such that second springend 54 is displaced away from second seat 76. The design of actuator 46facilitates convenient use thereof. More particularly, since actuator 46is elongate it is easy to engage with the typical palm of a hand, and aconsiderable force can thereby be readily brought to bear on a surfacethereof.

Sheath 28 can thus be retained between second end 54 of cantileverspring 50, and second seat 76. Second seat 76 (FIG. 3), in the preferredembodiment includes two support portions 78 each having a "V" shapedconfiguration for providing firm support along portions of retainedsheath 28. As should be appreciated, second seat 76 serves the dualfunction of engaging the front end of actuator 46 when apparatus 10 isnot in use, and contributing to sheath 28 retention when device 10 isbeing used for unsheathing, syringe holding or resheathing. Securementof sheath 28 within chamber 38 may be further facilitated by providingsecond end 54 of cantilever spring 50 with an uneven edge 80 (e.g.,rounded serrations). Use of uneven edge 80 (FIG. 3) minimizes slippingof sheath 28 when spring second end 54 bears against a portion of thesame.

Use of cantilever spring 50 greatly enhances the ability of device 10 toretain typically employed sheaths. More specifically, experimentationhas found that an actuation force of no more than approximately 8 poundsneed be applied to actuator 46 to deflect cantilever spring 50 forinsertion of sheath 28, and that upon releasing spring 50 an averagesheath retention force of approximately 5 pounds can be achieved. Thatis, the ratio of change in force, i.e., change in actuation force andretention force, to change in spring 50 deflection is relatively low.This is due to the preferred initial non-linear configuration ofcantilever spring 50 and the substantially linear disposition thereof indevice 10, as described hereinabove. It should therefore be appreciatedthat through employment of cantilever spring 50, optimal sheathretention is achieved while minimizing the required actuation force. Itshould also be noted that the average sheath retention force of 5 poundswas selected to optimize retention of a typical sheath 28 duringselective disengagement thereof from hub 26 during unsheathing, yetprevent distortion of sheath 28 during periods in which it is disposedbetween cantilever spring 50 and second seat 76. It should be furthernoted that a retention force of 5 pounds provides adequate support forselective disconnection of needle assembly 22 from spigot 20, asdiscussed in further detail below.

Surrounding sheath receiving aperture 40 is a shield 82. As bestillustrated in FIG. 2, shield 82 is connected to housing 30 through useof snap fitting 32 and screw fitting 33 in the preferred embodiment.Shield 82 extends away from aperture 40 and is frusto-conically shaped.Surface 84 of shield 82 provides an area large enough to protect thehand (e.g., a diameter of approximately 4.6 inches) and serves to directneedle 24 toward receiving aperture 40 during use. Surface 84 has aperimeter edge 86 which includes angled edge portions 88. In thepreferred embodiment, each of angled edge portions 88 are provided atapproximately 17.5 degrees with respect to the longitudinal center axisof device 10. Consequently, apparatus 10 is inclined upward when placedon a flat surface. While in this position, apparatus 10 is capable ofeither holding sheath 28 alone or a sheath covered needle of syringe 12.As will be appreciated, the 17.5 degree angulation disposes apparatus 10for easy insertion of syringe 12. Additionally, when device 10 is beingused as a holder for syringe 12, the 17.5 degree angulation providesadequate clearance for plunger 16 and flange 18 with respect to the flatsurface. Finally when housing 30 is resting on a flat surface at a 17.5degree inclination, a space is provided between housing 30 and shield 82so that gripping portion 36 can be easily grasped by the user.

An aperture 94 is disposed in housing 30 to facilitate securement ofdevice 10 to a belt, hook or the like. That is, a strap or chain may befed through aperture 94 so that device 10 can be hung or secured duringperiods in which device 10 is not being used.

To remove sheath 28 (FIGS. 4A-C) from syringe 12 using device 10,gripping portion 36 of housing 30 is grasped in the palm of the hand.Actuator 46 is depressed (FIG. 4B) so that the front end of actuator 46deflects spring second end 54 away from second seat 76 to define an openpassageway between sheath receiving aperture 40 and internal chamber 38.The sheathed needle of syringe 12 is then inserted through aperture 40(FIGS. 4B and 4C) until a desired length of sheath 28 is containedwithin internal chamber 38. As will be appreciated by those skilled inthe art the positioning of sheath 28 within chamber 38 is not criticalas long as substantially any location disposed along the length ofsheath 28 is positioned between spring second end 54 and supports 78 ofsecond seat 76. It should be appreciated that if sheath 28 is accidentlyinserted past spring second end 54, it may be easily retrieved viaaperture 42. Upon positioning sheath 28 accordingly, pressure isreleased from actuator 46, thus causing cantilever spring second end 54to bear against sheath 28 and securing supports 78 against sheath 28such that sheath 28 is held firmly in place. Syringe 12 is then pulledaway, and the retaining force of spring 50 facilitates the separation ofsheath 28 from syringe spigot 20. Upon unsheathing, there is no need forthe user to continue holding device 10, so the same is typically placedon a flat surface until resheathing is desired.

The resheathing process is initiated by grasping gripping portion 36 inthe palm and inserting needle 24 into sheath 28 until sheath 28 is pressfitted against hub 26. Once needle assembly 22 is adequately insertedinto sheath 28, actuator 46 is depressed so that spring second end 54 isdirected away from a corresponding portion of sheath 28 and the same iseffectively disengaged. Syringe 12 is then removed from device 10 andactuator 46 is released such that the front of actuator 46 and springsecond end 54 again engages second seat 76, and receiving aperture 40 isblocked off.

It should be appreciated that apparatus 10 can be advantageously used asa holder for syringe 12. For example, rather than removing syringe 12from device 10 after initially inserting syringe 12 and releasingactuator 46, it is possible, and often desirable, to simply place thedevice 10, with sheath covered needle 24 of syringe 12 therein, down ona flat surface until use of the syringe is desired. Similarly, ratherthan depressing actuator 46 and pulling syringe 12 away after insertingneedle assembly 22 into secured sheath 28 for resheathing, it may bedesirable to simply set device 10, with sheath covered needle 24 ofsyringe 12 therein, down on the flat surface until further use isdesired. This procedure is particularly apt for multiple syringe useapplications.

Due to its construction, apparatus 10 is advantageously suited fordisconnection of needle assembly 22 and use with any appropriatedisposal receptacle. Disposal of needle assembly 22 along with sheath 28may be performed anytime after completing the resheathing process. Fordisconnection, syringe 12 is grasped along a section thereof, possiblyat flange 18, and pulled away from the apparatus 10, while if necessary,slightly twisting syringe 12. As noted above, due to the 5 poundsretention force applied to sheath 28 in the preferred embodiment 10, thesheath 28 and needle assembly 22 are both firmly retained during thedisconnection step. Subsequent to disconnection, apparatus 10, withsheath covered needle assembly 22 retained thereby, can be positionedover the disposal receptacle such that when actuator 46 is depressed,sheath 28 is disengaged and sheath covered needle assembly 22 falls intothe receptacle. As should be appreciated, during the above-describeddisconnection and disposal processes the fingers do not touch thepotentially contaminated needle assembly 22 or sheath 28. Thus, thepossibility of undesired cross-contamination is minimized andconvenience is served.

From the foregoing description, it will be appreciated by those skilledin the art that modifications or improvements may be made to thepreferred embodiments disclosed herein without departing from theconcepts disclosed. The scope of protection afforded is to be determinedby the claims which follow and the breadth of interpretation that thelaw allows.

What is claimed is:
 1. An apparatus for selectively retaining a needlesheath comprising:a housing; a gripping portion at least partiallydefined by said housing and adapted to be gripped by the hand of a user;and retaining means positioned at least partially within said housingand comprising an external portion that partially defines said gripingportion and that is of a longitudinal length sufficient to allow atleast the majority of a user's hand to apply pressure thereto forselectively engaging and disengaging a sheath when said gripping portionis gripped transversely by the user.
 2. The apparatus of claim 1,further comprising:a first opening at a first end of said housingadapted to receive said sheath; an internal chamber within said housingand communicating with said first opening; and, wherein said externalportion of said retaining means is defined by a controlling member, andsaid retaining means further comprises a separate, substantiallyshielded resilient means in movable contact with said controlling memberand positioned to engage and retain said sheath adjacent to said firstopening within said internal chamber during use.
 3. An apparatus forselectively retaining a needle sheath comprising:a housing; a grippingportion at least partially defined by said housing and adapted to begripped by the hand of a user; retaining means positioned at leastpartially within said housing for selectively engaging and retaining thesheath; and controlling means for permitting the user to selectivelycontrol engagement between said retaining means and said sheath, saidcontrolling means partially defining said gripping portion and saidcontrolling member being pivotally interconnected with said housing atone end of said housing.
 4. The apparatus of claim 2, further comprisinga second opening at a second end of said housing and communicating withsaid internal chamber.
 5. An apparatus for selectively retaining aneedle sheath comprising:a housing; a gripping portion adjacent to begripped by the hand of a user; an opening at one end of said housingadapted to receive said sheath; and a shield extending laterally awayform said opening and having at least one flat peripheral edge portionto restrict rotational movement of the apparatus when placed upon asupport surface, wherein said one flat peripheral edge portion lies in aplane that transverses the longitudinal center axis of the apparatusrearward of said opening.
 6. The apparatus of claim 5, wherein saidshield is frusto-conical.
 7. An apparatus for selectively retaining aneedle sheath comprising:housing means; and resilient meansinterconnected with said housing means for selectively retaining asheath by transversely engaging a limited sidewall portion of saidsheath, wherein said engagement is limited to a plane that transversesthe longitudinal center axis of the sheath; and, controlling meansoperatively associated with said resilient means for permitting a userto selectively control retaining engagement and disengagement of saidresilient means and said sheath by applying pressure to said controllingmeans to deflect said resilient means, wherein the length of saidcontrolling means is greater than the length of said limited sidewallportion and wherein sheath retention forces imparted by said resilientmeans are concentrated to said limited portion to restrict longitudinal,lateral and rotational movement of said sheath during use of theapparatus.
 8. The apparatus of claim 7 wherein said resilient meanscomprises a spring means having a surface particularly adapted forrestrictingly engaging said sheath.
 9. The apparatus of claim 8, whereinan edge portion of said spring means engages said sheath and whereinsaid edge portion includes two or more projections.
 10. The apparatus ofclaim 8 wherein said spring means is elongated and includes an end whichis interconnected with said housing in a cantilever manner about an axissubstantially parallel to the longitudinal center axis of the apparatus.11. The apparatus of claim 10, wherein said elongated spring means has anon-linear shape prior to assembly of the apparatus, wherein uponassembly of the apparatus one end of said cantilever spring is deflectedin a first direction to a first position, and wherein during operationof the apparatus said one end of said cantilever spring is furtherdeflected in said first direction.
 12. An apparatus for selectivelyretaining a needle sheath comprising:housing means; and engaging meansinterconnected with said housing for selectively engaging said sheath,wherein said engaging means comprises resilient means and a seat member,wherein said resilient means bears against a portion of said seat memberwhen the apparatus is not in use, and wherein said resilient means isdeflected to bear against a limited portion of said sheath positionedbetween said resilient means and said seat member during use of theapparatus.
 13. An apparatus for selectively retaining a needle sheathcomprising:housing means; and engaging means interconnected with saidhousing means for selectively retaining a sheath wherein said engagingmeans comprises a seat member having at least one V-shaped supportportion for engaging said sheath; and controlling means, for permittinga user to selectively control retaining engagement of said engagingmeans and said sheath.
 14. An apparatus for selectively retaining aneedle sheath comprising:a housing; retaining means interconnected withsaid housing for selectively engaging and retaining a sheath insertedinto said housing, comprising:resilient means; and, support meanspositioned in opposing relationship to said resilient means wherein saidsheath can be supported by said support means and retainingly engagedbetween said resilient means and said support means substantiallyintermediate of the ends of said sheath during use of said apparatus.15. An apparatus for selectively retaining a needle sheath comprising:ahousing; and, retaining means interconnected with said housing forselective retaining engagement and disengagement of a sheath in thesubstantial absence of simultaneous contact and relative movementbetween said retaining means and said sheath, said retaining meanscomprising a resilient member having a deflectable end for engaging saidsheath and particularly adapted for griping a peripheral portion of saidsheath to restrict both longitudinal, lateral and rotational movement ofsaid sheath relative to said apparatus, and said retaining means furthercomprising a seat member in opposing relationship to said surface. 16.The apparatus of claim 14, wherein said seat means is positionedsubstantially entirely on one side of a plane centered about thelongitudinal center axis defined by said opening.
 17. The apparatus ofclaim 14, wherein said support means comprises two spaced supportsurfaces which each include a recess to receive said sheath and restrictlateral movement during use.
 18. The apparatus of claim 17 wherein saidresilient means laterally engages said sheath in a region substantiallybetween said two support surfaces.